Quantifying the relation betwen jet meandering and extreme events

The Eddy-driven jet meandering has been hypothesized to increase due to climate change. This meandering frequently induces slow-moving patterns of low and high pressure anomalies, potentially causing extreme weather events such as droughts, flooding, heat waves and cold spells. However, the quantitative link between the jet’s meandering and storms development is still lacking, as well as a conclusive mechanism for the effect of climate change on the jet’s meandering. In this study, we first separate the physical components in the atmospheric complex system using an idealized global circulation model. We outline the connection between the decreasing equator-to-pole temperature gradient due to Arctic amplification and the meandering of the jet. As the meridional temperature gradient decreases, the eddy-driven jet slows and its meridional layout widens. By Lagrangian tracking cyclones and anticyclones, we link the jet meandering to the formation of cyclones and anticyclones. Looking at more realistic simulations, using CMIP6 data and applying a similar analysis we find analogous linkage between the meandering of the jet and storm genesis under the SSP585 scenario. We will present both our new methodology and results connecting jet meandering and extreme events.